html,
body {
  width: 100%;
  height: 100%;
  padding: 0;
  margin: 0;
}
.content-box {
  position: relative;
  /* 实现左侧固定的规则 */
  padding-left: 200px;
  height: 100%;
  min-width: 220px;
}
/* 左 */
.l-box {
  /* 实现左侧固定的规则 */
  position: absolute;
  width: 200px;
  height: 100%;
  top: 0;
  left: 0;
}
/* 右 */
.r-box {
  background: #bababa;
  height: 100%;
}
